According to the environmental control model (Whittaker, 1956 Bray &Ĭurtis, 1957 Hutchinson, 1957), environmental characteristics are the external forces Several forces, some of which are external whereas others are intrinsic to theĬommunity. It is now understood that species distributions result from the combined action of Which should be compared to the scale of the phenomenon under study. So, gradients or patches displayedīy maps may only be interpreted with respect to the scale of the sampling programme, Most field studiesĬover only a part of any variable’s spatial structure. Structure is smoothly continuous or marked by sharp discontinuities. Spatial variation of an ecological variable in the form of a map shows whether the
Spatial scales - from micrometres to continent and ocean-wide scales. Understand the mechanisms that control species distributions. Patches (such as tree groves, phytoplankton patches, and animal herds) or gradients.Įcologists examine the spatial patterns of species or assemblages in order to Most ecological patterns may be described as either Give rise to spatially recognizable structures which may display spatial patterns and be (called mensurative experiments by Hurlbert, 1984), whereas underlying processes canīe studied by manipulative experiments (Subsection 10.2.3). Spatial patterns are studied through surveys
The analysis of spatial patterns is of prime interest to ecologists because mostĮcological phenomena investigated by sampling geographic space are structured byįorces that have spatial components.
0 kommentar(er)
